FtG was effective -- at starting wars and killing people to further his own dynastic ambitions. People who wanted to live in peace and prosperity would not agree he was the "right leader"
Well sure, George Washington was a very violent fellow as well but I usually don't see that levied against him. Same with Winston Churchill. You might want to learn more about Frederick, here's a primer: http://en.wikipedia.org/wiki/Frederick_The_Great
